The present invention relates to mechanical switches in general, and more particularly to improvements in mechanical switches of the type known as latching and momentary switches. As used in this description, the term "latching switch" denotes a mechanical switch wherein each second displacement of a knob, pushbutton, lever or rotary actuating element is followed by movement of a circuit-completing manner (e.g., a reciprocable plunger) to free position. The term "momentary switch" denotes mechanical switches wherein each and every displacement of a knob or the like is followed by movement of the circuit-completing member to free position.
Certain presently known mechanical latching or momentary switches comprise a housing which is rigidly connected to or made integral with a frame for the actuating element. The actual switching element or elements (e.g., one or more microswitches) are mounted at that end of the housing which is remote from the frame. Each movement of the circuit-completing member from its free position to its operating position results in actuation of each and every switching element. That portion of the housing which is adjacent to the frame is formed with external threads adapted to mate with the internal threads of a nut. When a switch of the just outlined character is to be installed in a control panel or the like, the nut is detached from the housing and the housing is introduced into and through a suitably configurated opening into the interior of the structure including the control panel. The insertion is terminated when the frame abuts against the outer side of the control panel. The nut is thereupon placed into mesh with the housing at the inner side of the control panel so that it clampingly engages the control panel opposite the frame. This insures that the switch is incapable of performing any stray movements with respect to the control panel.
A drawback of the just described conventional switch is that its component parts must be taken apart prior to mounting of the switch in or on a control panel or the like. Moreover, each switch must be installed individually; this is especially cumbersome when a control panel is to support a large number of switches, e.g., a long row or another array of latching and/or momentary switches.
It is further known to provide the externally threaded housing of a latching or momentary switch with an internally threaded neck portion which extends forwardly or outwardly beyond the external threads. When the switch is to be installed in a control panel or the like, the neck portion of the housing is caused to pass from the inside through a suitable bore or hole of the control panel. In the next step, the person in charge places the frame against the outer side of the neck portion so that the frame abuts against the outer side of the control panel. The frame is held in such position by a ring having external threads mating with the threads of the neck portion. In the next-following step, the aforementioned nut is applied to bear against the inner side of the control panel and to maintain the frame in clamping engagement with the outer side of the control panel. The just described conventional switches are not suited for use in combination with one or more additional switches; moveover, their manufacturing cost is high and the mounting of such switches in a control panel or the like is a tedious and time-consuming operation.